| Title | Hydrothermal Evolution of the Nesjavellir Hightemperature System, Iceland |
|---|---|
| Authors | Hjalti Franzson |
| Year | 2000 |
| Conference | World Geothermal Congress |
| Keywords | Iceland, Nesjavellir, geothermal system, mineral deposition, geothermal evolution |
| Abstract | The abundant vesicle and vein fillings in the Nesjavellir hightemperature field in SW-Iceland allows the thermal evolution to be studied. These time related sequences show a geothermal system evolving from a low-temperature condition to a high-temperature one, probably less that 100,000 years ago, associated with intrusives of dioritic composition. A progressive heating follows along NE-SW trending faults and eruptive fissures reaching a maxima, possibly ~5000 years ago. As the system cooled calcite was deposited. At present, the geothermal system is undergoing heating in southern part of the field, east of the Kyrdalsbrunir eruptive fissure. |